Edgar Diaz, 21, of the 5600 block of West Grand Avenue, is charged with attempted first-degree murder and aggravated battery, police said. He was arrested last week and identified by witnesses, police said.

The prosecutor was on his way to meet a friend to fish along the lakefront around 7 p.m. Sept. 14 when he saw two people shouting at the couple and told them to stop, according to Sally Daly, a spokeswoman for the state's attorney's office. "They turned on him and ran at him."

The prosecutor, 31, was cut near the left eye, on his side and under his right arm, officials said.

Teddy Wozny, 27, said he and the prosecutor were supposed to meet at Diversey Harbor that evening to test out a new fishing grip. The two have been friends after meeting a couple of years ago on an online forum for Chicago area fishing enthusiasts called WindyCityFishing.com.

Wozny said he parked his car about 7 p.m. and was coming back from paying the meter.

"I had just texted [the victim] a couple minutes before and he responded, so I had no idea anything was going on," Wozny said. "All of a sudden I saw him limping out from under the tree line in the park. When I saw his face, I was like 'Holy cow.' "

His friend was bleeding from a cut under his eye and had stab wounds under his arm, Wozny said. The two walked to the nearby St. Joseph Hospital, and then he went with him as he was transported to Illinois Masonic Hospital. Wozny said his friend was released late Friday and is resting at home.

The victim told Wozny he was walking through the park and saw two people chasing after two men and yelling at them.

"He said they were chasing them, full-on running, and the two (harassed) guys were screaming for help," Wozny said. His friend told him he yelled "Knock the f--- off!". They wheeled around and immediately ran right at him.

"[The victim is] not a small guy. He's 6 feet, 230 pounds, so he grabbed the first kid and got him in a choke hold, and was trying to keep that guy between him and the second guy," Wozny said. "Then he slipped on the grass and went down, and they got the best of him."

The victim was hit with a beer bottle while on the ground but was still conscious. He told Wozny he yelled to his attackers, "OK, OK ... you made your point. It's done." One of them said, "No this isn't done," and that's when his friend believes he got stabbed, according to Wozny.

Reached by phone at the time, the prosecutor declined to talk about the incident. The prosecutor joined the state's attorney's office in 2008 and is assigned to juvenile justice, Daly said.

Diaz has a previous conviction for unlawful use of a weapon and has a pending criminal case for felony involving drugs, possession of a handgun by a felon and armed violence, according to court records.